Use almond milk and lemon juice instead of buttermilk at 1 tbsp lemon juice per cup of almond milk, rested 5 minutes. Buttermilk and almond milk and lemon juice do similar work in a recipe, but they are not identical, and the ratio is what makes the swap succeed. This guide gives the exact ratio, an equivalence table for every amount you will need, what changes in the finished dish, and when you should not make the swap at all. All ratios on this page come from the CookScale substitution data, and every result is approximate; taste the dish before serving, and adjust the seasoning if the swap changes the flavour.
Buttermilk to Almond milk and lemon juice: equivalence table
The table below scales the ratio — 1 tbsp lemon juice per cup of almond milk, rested 5 minutes — to every amount you will need, from a quarter of a cup up to three cups. Use the row that matches your recipe, and do not guess the scaling in your head, because a small error in the ratio grows with the size of the recipe.
| Buttermilk needed | Almond milk | Lemon juice | Rest |
|---|---|---|---|
| 1/4 cup | 1/4 cup | 3/4 tsp | 5 minutes |
| 1/2 cup | 1/2 cup | 1 1/2 tsp | 5 minutes |
| 1 cup | 1 cup | 1 tbsp | 5 minutes |
| 2 cups | 2 cups | 2 tbsp | 5 minutes |
| 3 cups | 3 cups | 3 tbsp | 5 minutes |
When a recipe calls for an amount that is not in the table, scale the ratio proportionally: work out how many cups of buttermilk the recipe needs, then multiply the ratio by that number. For a single cup, the ratio is exactly as stated; for half a cup, halve it; for two cups, double it. Keep the recipe scaler open while you cook, and you can scale the whole recipe, including the substitution, in one step.
What changes when you use almond milk and lemon juice instead of buttermilk
Almond milk soured with lemon juice is the dairy-free version of buttermilk, and it behaves the same way in baking: the acid activates the baking soda, tenderises the crumb and adds a tang. The main differences are the flavour and the richness: almond milk is thinner and lighter than dairy buttermilk, and it has a light, nutty note, while the lemon juice adds a faint citrus tang. The result is a lighter bake with a slightly nuttier flavour, which suits a vegan pancake or a dairy-free muffin. The rise is the same, because the acid does the same work, and the crumb is just as tender. In a marinade, the soured almond milk tenderises the meat or the tofu in the same way as buttermilk, but the flavour is lighter. In a dressing, the difference is bigger, because almond milk is thin and the dressing will be runny.
When not to substitute buttermilk with almond milk and lemon juice
Do not use plain milk — without acid, baking soda will not activate and the bake can taste soapy. That rule is the most important part of this page, because a substitution that works in one recipe can fail badly in another. Buttermilk does a specific job in each recipe, and the swap only works when the substitute can do the same job. In a recipe where buttermilk is the main structure — where it holds the bake together, or where its flavour is the point of the dish — the substitute will not do, and it is better to wait until you have the real ingredient, or to choose a different recipe. In a recipe where buttermilk is a supporting ingredient, where it adds moisture, richness or flavour but does not carry the dish, the swap usually works well. The test is simple: if removing the buttermilk would ruin the recipe, do not substitute it; if the recipe would still work without it, the substitute is probably safe.
Why this swap works
The acid in buttermilk activates baking soda and tenderises crumb; any acidic milk works the same way. That is the principle behind the swap: the substitute does the same chemical or structural job as the original, even though it looks and tastes different. The acid in an acidic substitute activates baking soda, the fat in a fatty substitute shortens a dough, and the liquid in a liquid substitute hydrates the flour. When the substitute does the same job, the swap works; when it does a different job, the swap fails. The ratio on this page is the amount that makes the substitute do the same job as the original, and it is worth following exactly, rather than guessing, because a small error in the ratio changes the job the substitute does.
Worked examples: buttermilk to almond milk and lemon juice in real recipes
1. Vegan pancakes without dairy
A stack of vegan pancakes for four needs a cup of buttermilk, so stir a tablespoon of lemon juice into a cup of unsweetened almond milk and leave it for five minutes. The almond milk thickens slightly and may curdle a little, which is normal. Pour the soured almond milk into the batter exactly where the buttermilk would have gone, and cook the pancakes over a medium heat. The lemon adds a faint citrus note that suits pancakes, and the acid activates the baking powder, so the pancakes turn out light and fluffy.
2. A dairy-free muffin batch
A batch of dairy-free muffins needs two cups of buttermilk, so stir two tablespoons of lemon juice into two cups of unsweetened almond milk and leave it for five minutes. The soured almond milk gives the muffins the same tang and the same lift as buttermilk, and the crumb is slightly lighter, because almond milk is thinner than dairy milk. Use unsweetened almond milk, and do not change anything else in the recipe, because the swap is a straight replacement for the liquid.
3. A dairy-free marinade for tofu
A marinade for tofu needs a cup of buttermilk, so stir a tablespoon of lemon juice into a cup of unsweetened almond milk and leave it for five minutes. The soured almond milk tenderises the tofu in the same way as buttermilk, because the acid breaks down the proteins, and the nutty note suits the tofu. Marinate the tofu for at least an hour, and turn it halfway through to coat it evenly, because the marinade is thinner than a buttermilk marinade.
How to make the swap
Pour the almond milk into a measuring jug, stir in the lemon juice, and leave the jug on the counter for five minutes. The almond milk will thicken slightly and may curdle a little, which is normal and exactly what you want: the curdling shows that the acid is working. Use the soured almond milk straight away, before it separates too much, and stir it into the batter exactly where the buttermilk would have gone. Use unsweetened almond milk, because sweetened almond milk adds sugar the recipe did not ask for. Use fresh lemon juice if you have it, because bottled lemon juice works but tastes slightly sharper. Do not skip the resting time, because the acid needs a few minutes to work on the milk.
Common mistakes
The most common mistake is using sweetened almond milk, which adds sugar the recipe did not ask for and can make a savoury dish taste odd. Use unsweetened almond milk. The second mistake is skipping the resting time and using the milk straight away, before the acid has had time to work. Rest it for five minutes, or the baking soda will not activate properly. The third mistake is using too much lemon juice, which makes the bake taste of lemon and can make the crumb too tender; one tablespoon per cup is enough. Finally, do not use this swap in a recipe where the richness of buttermilk matters, such as a creamy dressing, because almond milk is thin and the dressing will be runny and light.
Frequently asked questions
How do I make dairy-free buttermilk with almond milk?
Add 1 tablespoon of lemon juice per cup of unsweetened almond milk, and rest the mixture for 5 minutes. The almond milk thickens slightly and may curdle a little, which is normal and shows the acid is working. Use the soured almond milk straight away, and stir it into the batter exactly where the buttermilk would have gone.
Can I use sweetened almond milk for this swap?
It is better not to. Sweetened almond milk adds sugar the recipe did not ask for, which can make a savoury dish taste odd and a cake too sweet. Use unsweetened almond milk, and add your own sweetener separately, so you control the taste. The same rule applies to flavoured almond milk, which adds a flavour the recipe did not ask for.
Does soured almond milk activate baking soda?
Yes. The lemon juice makes the almond milk acidic, and the acid activates baking soda in exactly the same way as buttermilk, giving the bake its rise and its tender crumb. The rise is the same, and the crumb is just as tender, although the bake is slightly lighter, because almond milk is thinner than dairy milk.
Can I use this swap in a dressing?
It is not ideal. Almond milk is thin, so a dressing made with soured almond milk will be runny and light, and it will not have the richness of a buttermilk dressing. For a dairy-free dressing, a better choice is a plant-based yogurt, which is thicker and tangier, and gives a creamier result.
Is this swap suitable for a nut allergy?
No. Almond milk contains nuts, so it is not safe for anyone with a nut allergy. For a nut-free, dairy-free buttermilk, use oat milk or soy milk soured with lemon juice instead, which gives the same result without the nuts. Check the carton for allergen warnings, because some plant milks are made in factories that handle nuts.